Can Air In The Brake Line Cause A Caliper To Stick?

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The air in the brake line can cause a brake caliper to stick. Mostly, this occurs when the brake hose collapses internally.

As a result of this, whenever pressure is applied on the brake pedal, it will shove the brake fluid such that the braking system will function. Upon releasing the brake pedal, there will be no pressure left to overcome the collapse of the hose, as a result of which the caliper piston may not release.

The piston in any caliper is usually sliding calipers that move continuously whenever the brake pads start to wear.

The majority of them are equipped with a bracket. Again, commonly, 4 piston calipers bear 2 inboards and another 2 outboard opposing pistons as well. In addition, most 4 piston calipers commonly have a fixed position design.

Other notable and frequent causes of brake caliper sticking have to do with both its piston and brake hose. The piston is known to have a rubber boot put on it that lubricates as well as protects it from the elements.

Therefore, whenever this rubber is either torn or damaged, there is a strong possibility of both debris and rust being generated within the caliper. This means that the ability of the piston, in terms of sliding, will be significantly reduced.

On the other hand, whenever your brakes refuse to release, you should begin by inspecting to find out whether any of either the brake caliper or the brake pad is not seized. The tendency for this malfunction to happen is primarily due to the age of the system or rust.

Consequent to this, your vehicle may develop the tendency to pull to one side of the road whenever you depress the brake pedal.

Air easily gets access into the brake lines. However, this occurs mainly because brake fluid by nature is hygroscopic, which means that it can effectively absorb moisture from the atmosphere.

Consequently, any water in the brake fluid reduces its boiling temperature or point. Thus, heat can cause the brake fluid to boil and the steam so generated will equally leave air in the brake lines. A

You should know that brake fluid is incompressible as against air that can be easily compressed and which can also cause a spongy brake pedal or even worse than that.

It can now be easily seen that not only does air in the brake line cause the caliper to stick, it is also one of the commonest causes of the malfunction.

It is a mutually exclusive occurrence that whenever your brake pads begin to wear out, additional brake fluid will be required to keep the entire braking system well supplied.

However, if you fail to regularly inspect your brakes, you may not know that as it works harder and for longer to depress the brake pads, the air is easily taken into the braking mechanism, which causes your brakes to become very spongy, ineffective, and functionless.

Table Of Contents

What causes the caliper to stick when air gets into the brake line?

Whenever you depress the brake pedal, the applied pressure will press on the brake fluid which will, in turn, cause the brake to be applied on the wheels of the vehicle.

However, curiously, if you have significant air in the brake line, there will be no pressure to overcome the collapse of the hose after you have released the brake pedal, and consequently, the caliper piston will not release.

How does air get into the brake line?

First, brake fluid is said to be hygroscopic, which means that it easily absorbs moisture or water from the atmosphere.

When water gets into the brake fluid, it lowers its booking point, which means that the possibility of the fluid boiling at lower temperature increases.(Read Also: How Many Times Can Brake Rotors Be Resurfaced?)

eat will cause the brake fluid to boil, and the steam so produced leaves the air in the brake lines.

Since brake fluid is not compressible whereas air is readily compressed, pressing the brake pedal in this situation makes it feel spongy such that it can go to the floor without any positive impact on the vehicle.

Second, air can get into your brake line due to negligence too. For instance, some people do not care to frequently monitor their brake systems, and as the brakes work assiduously to depress the brake pads, the air is unfortunately taken into the system. It is this air that gives your brake pedal a spongy feel.

Can a caliper stick without air enter the brake line?

Yes, your brake caliper can stick without necessarily any air in it. This is primarily because some other common causes of caliper sticking aside from air are prevalent.

To be more specific, other very regular causes of caliper sticking are the brake piston and hose. Specifically, the hose is equipped with a sort of rubber boot that both protects and lubricates the piston. (Read Also: Do Black Brake Rotors Stay Black?)

Should this rubber get either torn or damaged, it will lead to debris and rust forming inside the caliper which implies that the sliding abilities of the piston will reduce. So, yes, your brake caliper can stick even without any air trapped in it.

How do I tell if air enters the brake line?

It is indeed very easy to tell the presence of air in your brake line. Firstly, when air eventually gets into your brake line, the brake pedal feels kind of spongy when pressed.

A spongy brake pedal feels uncomfortably soft and is very ineffective. Secondly, the air in the brake pedal commonly enables the brake pedal to be pressed down to the floor of the vehicle without any tangible influence on braking effectiveness.

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Aside from air entering the brake line, what else can cause a caliper to stick?

There are other very common reasons why your caliper may stick apart from air getting trapped in it. One, your brake caliper can easily stick if there is any malfunction in the brake hose.

Two, calipers also stick whenever there are any issues with the brake piston too. The piston in this situation may not lubricate parts of the braking system as it should, and eventually, the brake caliper may refuse to bulge.

Frequently asked questions(FAQ)

What causes the brake caliper to fail?

Your brake caliper will easily fail under certain conditions. One, it will fail when there is a malfunction or damage to either the brake hose or piston.

Secondly, your caliper can fail if your brake pads are getting abnormally worn out. In some cases, your calipers may even fail when air is trapped in the brake line as well.

Finally, to prevent the brake caliper from failing, you should regularly monitor your brake system such that you can detect any malfunction early and attend to it before it worsens either yourself or with the help of auto specialists. (Read Also: Can Brake Drums Warp?)

How do you fix a sticking brake caliper?

Brake calipers can easily get stuck due to various reasons, much of which we have discussed earlier in the article.

Therefore, it becomes expedient that we should look at how to resolve any issues of sticking brake calipers. However, before you can fix any stuck brake calipers, certain tools and precautions are very necessary.

First, park the vehicle at a location safe from interfering with other motorists on the road. Places you should not park on include slopes, corners, or close to the highways. Those mandatory tools you may need are wheel spanners, Jack and jack stands, as well as a clean cloth or paper towel.

Seven very simple steps are important in fixing stuck brake calipers as follows:

Step 1

First of all, you should jack up the car to give you access to its wheels.

Step 2

Thereafter, proceed to remove the affected wheel(s) of the vehicle.

Step 3

Next, with the aid of a clean cloth or paper towel, you should carefully clean the brake pads of any dust, grime, or debris on them.

Step 4

After accomplishing all the steps above, now is the time to remove both the brake caliper and its pads from the wheels of the vehicle.

Step 5

Now, you should clean the brake caliper itself since it has been removed and hence you have unfettered access to it.

Step 6

This step involves providing adequate lubrication to your brake calipers, pins, and slides. Doing this will ensure that your brake system works as smoothly and efficiently as it ought to.

Step 7

Finally, you should carefully reinstall all the component brake parts you have removed earlier on, such as the calipers, brakes, and even the wheels as well.